Table 3: Simulation study results based on 500 simulated trials. Sample size and treatment effects as specified in Table 2. Statistical properties of the 2-subgroup direct assignment option design with 1 IA (DAD-1) versus a 2-subgroup balanced randomized design with 1 interim analysis (BRD-1). One-sided and for the subgroup main effects; two-sided for the post-hoc test for an interaction effect.